A mathematically assisted reconstruction of the initial focus of the yellow fever outbreak in Buenos Aires (1871)

We discuss the historic mortality record corresponding to the initial focus of the yellow fever epidemic outbreak registered in Buenos Aires during the year 1871 as compared to simulations of a stochastic population dynamics model. This model incorporates the biology of the urban vector of yellow fever, the mosquito Aedes aegypti, the stages of the disease in the human being as well as the spatial extension of the epidemic outbreak. After introducing the historical context and the restrictions it puts on initial conditions and ecological parameters, we discuss the general features of the simulation and the dependence on initial conditions and available sites for breeding the vector. We discuss the sensitivity, to the free parameters, of statistical estimators such as: final death toll, day of the year when the outbreak reached half the total mortality and the normalized daily mortality, showing some striking regularities. The model is precise and accurate enough to discuss the truthfulness of the presently accepted historic discussions of the epidemic causes, showing that there are more likely scenarios for the historic facts.Comment: 25 pages, 12 figure

Role of Conical Intersections on the Efficiency of Fluorescent Organic Molecular Crystals

Organic molecular crystals are attractive materials for luminescent applications because of their promised tunability. However, the link between the chemical structure and emissive behavior is poorly understood because of the numerous interconnected factors which are at play in determining radiative and nonradiative behaviors at the solid-state level. In particular, the decay through conical intersection dominates the nonadiabatic regions of the potential energy surface, and thus, their accessibility is a telling indicator of the luminosity of the material. In this study, we investigate the radiative mechanism for five organic molecular crystals which display a solid-state emission, with a focus on the role of conical intersections in their photomechanisms. The objective is to situate the importance of the accessibility of conical intersections with regards to emissive behavior, taking into account other nonradiative decay channels, namely, vibrational decay, and exciton hopping. We begin by giving a brief overview of the structural patterns of the five systems within a larger pool of 13 crystals for a richer comparison. We observe that because of the prevalence of sheet like and herringbone packing in organic molecular crystals, the conformational diversity of crystal dimers is limited. Additionally, similarly spaced dimers have exciton coupling values of a similar order within a 50 meV interval. Next, we focus on three exemplary cases, where we disentangle the role of nonradiative decay mechanisms and show how rotational minimum energy conical intersections in vacuum lead to puckered ones in the crystal, increasing their instability upon crystallization in typical packing motifs. In contrast, molecules with puckered conical intersections in vacuum tend to conserve this trait upon crystallization, and therefore, their quantum yield of fluorescence is determined predominantly by other nonradiative decay mechanisms

LC–MS/MS Analysis of the Emerging Toxin Pinnatoxin-G and High Levels of Esterified OA Group Toxins in Galician Commercial Mussels

The occurrence of marine harmful algae is increasing worldwide and, therefore, the accumulation of lipophilic marine toxins from harmful phytoplankton represents a food safety threat in the shellfish industry. Galicia, which is a commercially important EU producer of edible bivalve mollusk have been subjected to recurring cases of mussel farm closures, in the last decades. This work aimed to study the toxic profile of commercial mussels (Mytilus galloprovincialis) in order to establish a potential risk when ingested. For this, a total of 41 samples of mussels farmed in 3 Rías (Ares-Sada, Arousa, and Pontevedra) and purchased in 5 local markets were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS). Chromatograms showed the presence of okadaic acid (OA), dinophysistoxin-2 (DTX-2), pectenotoxin-2 (PTX-2), azaspiracid-2 (AZA-2), and the emerging toxins 13-desmethyl spirolide C (SPX-13), and pinnatoxin-G (PnTX-G). Quantification of each toxin was determined using their own standard calibration in the range 0.1%–50 ng/mL (R2 > 0.99) and by considering the toxin recovery (62–110%) and the matrix correction (33–211%). Data showed that OA and DTX-2 (especially in the form of esters) are the main risk in Galician mollusks, which was detected in 38 samples (93%) and 3 of them exceeded the legal limit (160 μg/kg), followed by SPX-13 that was detected in 19 samples (46%) in quantities of up to 28.9 μg/kg. Analysis from PTX-2, AZA-2, and PnTX-G showed smaller amounts. Fifteen samples (37%) were positive for PTX-2 (0.7–2.9 μg/kg), 12 samples (29%) for AZA-2 (0.1–1.8 μg/kg), and PnTX-G was detected in 5 mussel samples (12%) (0.4 μg/kg–0.9 μg/kg). This is the first time Galician mollusk was contaminated with PnTX-G. Despite results indicating that this toxin was not a potential risk through the mussel ingestion, it should be considered in the shellfish safety monitoring programs through the LC–MS/MS methods.This research has received funding from the following FEDER co-funded grants. From Conselleria de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia, 2017 GRC GI-1682 (ED431C 2017/01). From CDTI and Technological Funds, supported by Ministerio de Economía, Industria y Competitividad, AGL2014-58210-R, AGL2016-78728-R (AEI/FEDER, UE), ISCIII/PI16/01830, RTC-2016-5507-2, and ITC-20161072. From the European Union POCTEP 0161-Nanoeaters -1-E-1, Interreg AlertoxNet EAPA-317-2016, Interreg Agritox EAPA-998-2018, and H2020 778069-EMERTOX. This work was also supported by the program “Juan de la Cierva 2016” from the Spanish Government. Paz Otero is recipient of a Postdoctoral Funding (Ref. IJCI-2016-27774)

Prevalence and associated factors with poor sleep quality in non-professional caregivers

This study aimed to determine the prevalence and associated factors of poor sleep quality in non-professional caregivers. With this purpose, cross-sectional data were collected from 201 dependent people’s family caregivers using the Pittsburgh Sleep Quality Index (PSQI), the Caregiver Burden Inventory (CBI), the General Health Questionnaire (GHQ-12), and an ad hoc questionnaire to obtain sociodemographic data. A total of 153 family caregivers were categorized as poor sleepers (PSQI > 5), resulting in a prevalence of poor sleep quality of 76.1% (95% CI = 70.5–82.5). Poor sleepers were more likely to care for persons with mental disorders (χ2 = 7.31; p < 0.01) and scored significantly higher on perceived burden (z = −4.44; p < 0.001), psychological distress (z = −6.24; p < 0.001), and in all the PSQI subscales (p < 0.001), compared with good sleepers (PSQI ≤ 5). By contrast, no differences were found between poor and good sleepers in age, gender, years providing care, and daily hours of care. Multiple linear regression analysis showed that the factors of caregiver burden (β = 0.15; p < 0.05) and psychological distress (β = 0.53; p < 0.001) were significantly associated with sleep quality in dependent people’s family caregivers. Cognitive-behavioral strategies to improve sleep quality in the primary health care of family caregivers are suggestedSpin-off of the University of Santiago de Compostela (Santiago de Compostela, Spain) “Xuntos. Psychological and Psychiatric Care” (2019-CE081-6)S

Ochratoxigenic aspergillus in wine grapes and ochratoxin a in wines from Northeast Brazil.

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